The present invention relates to a brake pad arrangement for a disc brake and to a method for producing such a brake pad arrangement. The brake pad arrangement comprises a brake pad carrier and a friction pad which is attached thereto and can be laid with a friction surface against a brake disc of the disc brake to obtain a friction effect, the friction pad being provided with a chamfer in at least one border region, which chamfer merges into the friction surface at a chamfer edge.
Brake pad arrangements of this type are known from the prior art. Thus, it has been realized that the provision of chamfers in the border region of the respective friction pads constitutes an effective measure for combating noise emissions which may occur during braking. Undesired noise emissions of this type are caused, for example, by friction-induced vibrations of the brake pad arrangement itself or other components of the disc brake arrangement. In the range of the resonant frequencies of the arrangement, clearly audible noises may occur, which are absolutely to be avoided to increase the driving comfort. For this reason, various possibilities for providing chamfers on the brake friction pads of known brake pad arrangements have been provided in the prior art. Thus, the prior art knows chamfers with substantially rectilinear chamfer edges which are free from kinks and which either run parallel to one another or are inclined relative to one another in the manner of segments with respect to the brake disc. According to a development in the prior art, chamfers having a kinked chamfer edge course are provided, so-called diamond chamfers, the term having been chosen based on a diamond cut with cut surfaces inclined relative to one another.
Diamond-shaped chamfers of this type are known, for example, from the document U.S. Pat. No. 5,535,859. Therein, it is described that the friction pad is provided with a chamfer cut both at its leading side and at its trailing side with respect to a rotational movement of a brake disc interacting with the friction pad, in which chamfer cut two chamfer surfaces inclined relative to one another are provided on each side of the friction surface. This configuration of the friction pad admittedly results in a considerable reduction of noise emissions. However, it is problematical in the case of this friction pad geometry that its production is relatively expensive because several grinding machining steps are required to achieve these chamfer surfaces inclined relative to one another. Especially in mass production, which has always to be optimised for economical production of brake pad arrangements of this type, the requirement of several working steps is, however, problematical because it is time-consuming and entails high costs.
A comparable situation is found in the brake pad arrangement according to U.S. Pat. No. 7,275,625 B2. This document too describes a friction pad of a brake pad arrangement with a diamond cut, i.e. with two chamfer surfaces inclined relative to one another and with a kinked course of the chamfer edges, which is subject to the problem of time-consuming and thus costly production. In this prior art, the problems of more simply configured chamfer cuts, in particular with chamfer edges free from kinks and running parallel to one another or v-shaped to one another, are also explained. Both geometries have the problem of comparatively small bearing surfaces and inadequate adaptation to the different circumferential speeds of the brake disc depending on the radius.
The document DE 10 2009 008 769 B3 shows a method and a device for producing brake pad carriers.